1. The Field of the Invention
The field of art to which this invention relates is pipes and tubular conduits with closures and plugs, laterally insertable.
2. Description of the Prior Art
Standard practice in the cutting off of gas service lines connected to the main line through a tee is to apply a steel closure plate to the cut-off tee and, while main line gas pressure is applied to the bottom of such closure plate, to weld the closure plate to the cut tee to form a seal thereon. This results in frequent escape of gas during the procedure of welding and development of a flame that harms welding operators, as well as development of cracks in such metal seal due to rapid cooling of such metal seals, which requires repeated testing for gas leaks and requires added welding steps, as does the development of holes through such initial welds by the line gas under pressure being applied to the zone of welding during welding.